In many electrical circuit applications, such as those used in radio transmitters, certain components must often be shielded from EMI and RFI energy that would otherwise detract from their performance or that would escape from such components and interfere with the proper operation of surrounding components. Ordinarily, such shielding is accomplished through provision of a grounded metal barrier. Where appropriate, this can and has included the provision of metal boxes comprised of two or more pieces (including the walls and top) that are positioned around the components to shield it and prevent EMI/RFI energy from passing through such barrier.
In general, such shields must be located on the circuit board substrate after the components themselves have been connected to the substrate, such as through reflow soldering. This is because reflow soldering techniques can not create a satisfactory bond between the components and the substrate when the components are surrounded by such a shield. Subsequent mounting of such shields, of course, represents additional processing time and cost, and a need exists for a way to provide adequate EMI/RFI shielding while simultaneously remaining compatible with reflow soldering techniques.